White Papers

White Papers

White Papers

White Papers

Corning has had a number of articles and papers published. These explain the fine points of some of our technology. We invite our customers to review these for a more detailed understanding of our products.

Electrically controlled VOAs either use ND filters or MEMs devices to attenuate the levels. Filters are slow and expensive, but they do work. MEMS devices are fast, but they are also expensive. Corning has found a way to utilize components proven in volume applications not in the fiber world to achieve a breakthrough in electrically controlled VOAs. Our units are not as fast as MEMs, but they offer excellent attenuation in a small package and at a price that cannot be met by either traditional filter or MEMS devices. These units are available either as discrete units for board mount, assemblies to handle multiple channel controls, or even one that can fit in the SFP footprint.

Corning's Compact CWDMs have revolutionized the use of the CWDMs into many networks. The inherently lower IL and increased reliability, coupled with the thinner footprint, has made them a great success. Applying these same techniques to DWDMs has also been accomplished. The optical requirements of the filters means that the footprint is slightly different, but it is possible to create compact DWDMs. However, the optical bench approach is limited to four channel units. Also, the PDL is slightly higher than traditional methods, and thus, this design is best suited for shorter distances. A good example would be expanding capacity in an existing CWDM pathway by adding a compact DWDM set inside one of the CWDM pathways.

Traditional CWDM technology uses concatenated three port filters. This is a proven technology with good results, but it suffers from a high number of components and high IL. Corning has developed a free space optics approach to CWDMs. Based on an optical bench concept, this design reduces the number of collimators which greatly improves IL. A major benefit is also a reduction in size. We call these new units compact CWDMs. Additional testing confirms that the new design also offers excellent reliability. Fewer parts and fewer connections makes for a more robust product.